This dissertation investigates disyllabic compound words in Vietnamese, an isolating tone language, using corpus linguistics and psycholinguistic experimental paradigms. Chapter 2 reports the construction of two corpora and a database of wide range of lexical variables. Chapter 3 discusses a visual lexical decision experiment with Vietnamese speakers, and Chapter 4 details the results of a visual lexical naming experiment, again with Vietnamese speakers. This dissertation supports the psychological status of the word as a single whole in non-decompositional model for reading Vietnamese compounds. The dissertation also documents the advantages of working with behavioral data from a single-subject with wide range of items. Finally, this dissertation demonstrates the involvement of phonology in silent reading through an analysis of the effects of lexical tone in the visual lexical decision task.